After finally reassembling my CT2 project bike I encountered several issues, one of which was the clutch. I had purchased new friction plates on Ebay (I know, I know) and scuffed up the steel plates with some emery paper on a piece of glass. I assembled everything as per diagram one below. The only thing different was the extra washer added behind the thrust bearing which is installed behind the outer thrust plate (see diagram two and photos). With this extra washer it appears that the thrust bearing never comes in contact with the thrust plate (a gap) and I’ve had two clutches (before rebuild) that were put together this way and were working just fine. 
The bike now has only 10 minutes on the new motor (new tranny oil) and the clutch slips at high rpms. The first thing I noticed was the oil (see photos). I took it apart and found more evidence of friction plate wear (see photos). The friction plates are 3.9mm thick (in spec.) and the springs are 31mm in length (also in spec.). So, I’m guessing that the slipping clutch is possibly due to:
1.      Non OEM friction plates (I know, I know), or
2.      The extra washer behind the needle bearing washer, or
3.      Saggy springs, or
4.      A combination of the above 

I greatly appreciate your advice in advance……….

Here are the diagrams and photos I couldn't fit in the first post.

Correct to my post above, " Without this extra washer it appears that the thrust bearing never comes in contact with the thrust plate (a gap) and I’ve had two clutches (before rebuild) that were put together this way and were working just fine."

You have it assembled right. In the drawing in No7 they've drawn it "i think" like that just to show it's a bearing & the thin washer is part of 'that bearing' so not shown separate. So yes, the thin washer part has to go as you have it, then the thick washer for the needles to bare against otherwise the needles would be running on the alloy of the clutch center--which is a no no. Alternatively if you reversed 'that' bearing the needles would bare on the cast center of the basket which is also a no no. You'll be good & nothing to do with clutch slip--whatever might be causing that. On the 360 for instance they ran 'that bearing' behind everything with the kickstart gear on the clutch, but in "74 they did away with it & just ran washers. Same with 175 & in "76 they just went to washers. I'm not a wealth of knowledge lol & went looking at partzilla as 'did' think they'd put 'that bearing' in the 'too hard' basket, maybe people kept assembling it wrong & destroying it. Can easily drop down during assembly & get squashed, especially in the 360Rt-250Dt where it was more out of sight in the back during assembly.

I know this has been talked about before, but the drawing is wrong in your pic No7 regarding clutch plates as need a fiber in first & a steel last for the end pressure plate to push on. That's if yours has an obvious flat area on the center for the first plate in to run against. On later clutches with a splined pressure plate you don't need a steel in last to take the drive. If there's room to 'add' a steel then that's one way of increasing spring pressure a very little bit but have to be careful there's still room for last steel in so it doesn't fall off the splines when clutch disengaged--unlikely but!!. Another thing i've come across--talking clutch plates--is--if not assembled how it should be & clutch center, 'call it hub', is if set too far back then the fiber plate ears can run out of slot before settling against the back of the hub to be compressed & drive. Could only happen if that annoying bearing was fitted behind the kick gear on the basket like shown in 360 drawings. Umm, forgotten the question now.

If you hover your mouse over my jpegs you can see the titles to each one. I understand that the plate order is incorrect in Diagram 2 (you call it "photo 7") as has been mentioned before here in the forum. I only include that diagram because it is easier to see the washer order in an exploded view rather than in profile like the correct version in Diagram 1. Sorry for the confusion.

Thank you for letting me know I have it assembled correctly. So why is my clutch is slipping?

Yep all good, comes up pic 7 of 9. But the big question is why does it slip. My AT1--now 175 slips but will only be 50 year old plates which a washer under each spring might overcome. I'm sure its been mentioned before that the stacked height of the plates needs to be enough so that the pressure plate compresses them without bottoming out on the hub. Good test would be to sit the pressure plate on without any plates, then measure as best yo can the gap where the plates fit. If the gap is less than the plate stack then you know you're good to go for being compressed. If measure exactly equal or more then it'll slip for sure. Sorry, getting interrupted here so hope it makes sense.

That oil looks very "black" considering it's only run for 10 mins, also, I'm sorry if I'm telling grandma how to suck eggs but is the oil specifically for wet clutches?

Make sure the new discs are 4mm and not 3mm thick.  The same disc came in different thicknesses.  I've received the wrong ones on ebay.  I read this yesterday and don't remember if you mentioned rubber rings.  I leave them out.

Here's the bearing Yamaha sells that RT325 described.  Comes with a washer that is not shown in diagram. 

 


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My CT3 has a recessed nut fitted . If you have it the wrong way it leaves a gap and of course the clutch slipps like hell.
I'm taking it apart tomorrow so ill send some pictures .